Information and studies on acid-base balance in medicine and research.

FAQ

General questions about acid-alkaline balance

Is it true that if the urine is alkaline, you do not have excess acid?

The urine pH level does not give reliable information about the body's acid-case status because urine pH depends greatly on food intake. In addition, it fluctuates according to the time of day (pH 5 - 8). Morning urine is usually more acidic than the urine produced throughout the day. Another factor is that less than 1% of the acid in the urine is excreted in the form of substances known as free acids. Yet, it is only these that can be measured with pH test strips. The remaining 99% of the acids excreted in the urine therefore cannot be determined using pH strips. For this reason, it is possible to assess acid-base status from the urine only by measuring total acid excretion in a 24-hour urine collection.

What are the underlying causes of acidosis?

To regenerate the buffering systems in the blood, the body needs alkaline-forming substances to reduce the diet-induced acid load. If sufficient alkalis are not present in the body, the body's own buffering systems become exhausted and latent acidosis occurs in the long term. Unfortunately, chronic acidosis manifests itself only in non-specific symptoms, such as fatigue, lack of drive, poor concentration and diminishing exercise capacity. However, skin and nail changes as well as muscle and joint pains can also be distinguishing features of an acid-base imbalance.

Does an acidosis make the skin worse?

Certain functions, e.g. the skin's defence function, can certainly be impaired by increased dietary acid loading of the body. In addition, there is evidence that acid-base balance plays a role in inflammatory disorders of the skin. A high-alkaline diet or dietary supplementation with alkaline minerals can therefore certainly have a positive effect on the skin's natural defences.

What happens if the body becomes too alkaline (from supplementing with an alkaline powder)?

Excess alkalinity cannot occur when kidney function is intact. Excess alkaline residues are excreted again in the urine.

Can weight loss also be achieved by deacidifying?

By a consistent change of diet to high-alkaline foods, it is also possible to lose weight in the long term. On a weight-loss diet, it is always advisable to take alkaline supplements in citrate form. The desired loss of fat stores leads to the production of substances known as keto acids, which can have a negative influence on the acid-base balance and lead to acidosis. This often makes itself felt in the form of a dieting or fasting healing crisis, when no further weight loss takes place.

How long does it take to deacidify the body?

It is difficult to generalise about this because it depends on each individual's condition and eating habits. In any case, a treatment with an appropriate alkaline product should take place over a period of 2-3 months.

Could an acidosis lead to an increased risk of bone breakages?

In the long term, chronic acidosis of the body can contribute towards the development of osteoporosis. This is because, in latent acidosis, alkaline minerals such as calcium and magnesium are released from the bones to neutralise excess acid in the body. In addition, chronic acidosis also influences the activity of bone cells. Numerous recent studies have now proven this connection. At the same time, studies have demonstrated that daily intake of citrates together with calcium and vitamin D3 can lead to an improvement in bone density.

How does chronic acidosis of the body manifest itself?

To regenerate the buffering systems in the blood, the body needs alkaline-forming substances to reduce the diet-induced acid load. If sufficient alkalis are not present in the body, the body's own buffering systems become exhausted and latent acidosis occurs in the long term. Unfortunately, chronic acidosis manifests itself only in non-specific symptoms, such as fatigue, lack of drive, poor concentration and diminishing exercise capacity. However, skin and nail changes as well as muscle and joint pains can also be distinguishing features of an acid-base imbalance.

How is a latent acidosis detected?

The acid-alkaline status can be assessed either by measuring 24-hour urine net acid excretion or from the blood's buffering capacity (Sander method, Jörgensen method, Stirum). However, only specific laboratories use these methods. People can assess their own acid-base status, best done through the diet because this is largely determined by regular habits and can thus provide information on possible latent acidosis. Our food table will help you do this.

Questions about diet and the food table

Which foods are alkaline?

Fresh fruit and vegetables, in particular, show base excess. You will find more detailed information in our Food table.

Is tap water acidic?

It is more a case of the opposite! The higher the proportion of minerals in tap water and mineral water, the greater their alkalinity. However, the proportion of phosphate and sulphate in the water must be low at the same time because otherwise the alkaline effect of the minerals will be partly neutralised again.

Is coffee or coffee substitute acid-forming?

Coffee and also espresso are aqueous plant extracts and even show slight excess alkalinity. However, this is often misrepresented in the popular press because coffee has a stimulating effect on stomach acid production, and this is often confused with its effects on the acid-base balance.

Is stomach acid buffered by alkaline foods?

In fruit, salads and vegetables, the minerals are overwhelmingly present in citrate form. Citrates do not react with stomach acid and are not absorbed until they reach the slightly alkaline environment of the small intestine and in this way enter the metabolism. Therefore, no buffering of stomach acid takes place.

How can someone with a fructose intolerance achieve acid-alkaline balance through diet?

Because fruit and also some types of vegetables are out of the question as alkaline-forming foods in someone with a fructose intolerance, it makes sense for an alkaline-forming product obtained from a pharmacy to be taken in this case. Make sure you choose a product containing mineral citrates!

Why are all fruits considered alkaline in the body? After all, kiwi fruit and oranges have an acidic pH!

Whether a food has an acidic or alkaline effect on the acid-alkaline balance always depends on the body's metabolism process and has nothing to do with an acidic taste. Foods with an acidic taste, such as oranges and kiwi fruit, are alkaline-forming because of their high content of organically bound minerals (e.g. potassium citrate). Whether a food has an acidic or alkaline effect on the body after being metabolised depends on the protein content.

Can I take a food supplement to prevent acidosis from occurring in the first place, or can such a generalisation not be made?

The usual diet today exposes the human body to approximately 50-100 mmol of excess acidity every day. This is mainly attributable to increased protein consumption accompanied by reduced fruit and vegetable consumption. If, for certain reasons, the alkaline requirement cannot be covered by the consumption of fruit, vegetables and salads, we recommend the use of an additional mineral supplement for acid-base balance. In this case, it is important for the minerals to be taken in citrate form.

Can the diet also simply be supplemented with high-alkaline foods to deacidify the body?

The 80:20 rule applies to acid-alkaline balance. This means that 80% alkaline foods and 20% acid-forming foods should be consumed at each meal.

Why do food tables differ so much?

Whether a food has an acidic or alkaline effect on the body after being metabolised depends on its protein content. Sulphur-containing amino acids (the smallest building blocks of protein) have an exclusively acidic effect in the body after being metabolised.

Most (older) food tables with acid-base values originate from the Bundeslebensmittelschlüssel [a database of food nutrients]. Excess acidity or alkalinity is calculated from the difference in base equivalents (sum of sodium, potassium, calcium and magnesium molecular fractions) and acid equivalents (sum of chlorine, sulphur and phosphorus molecular fractions) in foods, allowing for a rounding error.

A more accurate classification method is the PRAL (potential renal acid load) calculation model by Remer and Manz (1995), on which the food table here on the site is based and which reflects the state-of-the-art of science. According to this, foods are classified by their potential acid load on the kidneys, i.e. how high acid excretion is via the kidneys when certain foods are consumed. By comparison with the Bundeslebensmittelschlüssel database, this figure also takes into account the absorption rate of micronutrients in the bowel, their metabolism, and the acid produced in the body from sulphur-containing protein.

Is the alkaline effect reduced in frozen vegetables compared to fresh vegetables?

No alkalinity is lost in the freezing process. The same applies here as for cooking: the more gentle the defrosting process and preparation, the more alkalinity the vegetables retain.

Does the effect of foods change when they are cooked?

In itself, cooking does not reverse the alkaline effect. However, when vegetables are cooked, some of the bases leache into the cooking water (similar to what happens with vitamins). This should therefore be counter-balanced better or preference given to more gentle preparation methods, such as simmering or steaming with a little water.